We introduce a novel carbonate–bicarbonate eluent generation system in which CO₂ is introduced using programmable CO₂ pressures across a membrane into a flowing solution of electrodialytically generated high purity KOH. Many different gradient types are possible, including situations where gradients are run both on the [KOH] and the CO₂ pressure. The system is more versatile than current electrodialytic carbonate eluent generators and can easily generate significantly higher eluent concentrations (at least to 40 mM carbonate), paving the way for future higher capacity columns. Demonstrably purer carbonate–bicarbonate eluent systems are possible compared to manually prepared carbonate–bicarbonate eluents and with considerable savings in time. Performance in different modes is examined. The dissolved CO₂ is removed by a carbon dioxide removal device prior to detection. Best case noise levels are within a factor of 2–3 of best case suppressed hydroxide eluent operation. The eluent system allows particular latitude in controlling elution order/time of polyprotic acid analytes. Although CO₂ introduction is possible prior to hydroxide eluent generation, this configuration causes complications because of electroreduction of CO₂ to formate.

中文翻译：

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加压二氧化碳离子色谱自动编程制备碳酸氢盐洗脱液

我们介绍了一种新型的碳酸盐-碳酸氢盐洗脱液生成系统，该系统使用跨膜的可编程CO ₂压力将CO ₂引入电渗析产生的高纯度KOH的流动溶液中。可能有许多不同的梯度类型，包括在[KOH]和CO ₂上均进行梯度洗脱的情况压力。该系统比目前的电渗析碳酸盐洗脱液发生器更具通用性，并且可以轻松产生明显更高的洗脱液浓度（至少达到40 mM碳酸盐），从而为将来更高容量的色谱柱铺平了道路。与手工制备的碳酸盐-碳酸氢盐洗脱液相比，纯净的碳酸盐-碳酸氢盐洗脱液系统可以实现，并且可以节省大量时间。检查了不同模式下的性能。在检测之前，通过二氧化碳去除装置去除溶解的CO ₂。最佳情况下的噪声水平在最佳情况下抑制的氢氧化物洗脱液运行的2–3的范围内。洗脱液系统在控制聚丙烯酸分析物的洗脱顺序/时间方面具有特殊的自由度。虽然CO ₂可能在生成氢氧化物洗脱液之前进行引入，这种配置由于将CO ₂电还原为甲酸酯而导致复杂化。